CFU-F (colony-forming unit assay)

The efficiency with which primary cells form colonies is referred as Colony- Forming Units (CFU). This assay is one of the most important test to assess the quality of cell preparations. Many factors can cause variability in the Colony-forming unit (CFU) assay and for this reason it is very important to standardize the method. This capacity can be affected by long term culture or by medium and growth factors used for their expansion. Moreover a low level of endotoxin in all materials used is suitable because endotoxin could inhibit cell proliferation and clonogenesis. This assay is performed according to the European Pharmacopoeia (EP 6.0., 2.7 2.8).